I think the point of this blog and YouTube channel is to make these concepts approachable to the lay person, and introducing lots of technical jargon (relevant though it may be to actual geotechnical engineers) is not the best way to accomplish that.
Time to rename it from "Practical Engineering" to "Popular Engineering"? To me, the Practical handle is significant, so taking a few seconds to explain why soil compaction tests are vital makes practical sense.
The practical in his videos probably refer to the fact that he always explains things in physical models. It's very rare to just be theory. Thus, practical engineering demonstrations.